In textile yarn processing machines, such as two-for-one twisters, yarn is pulled from a hollow package carried by a stationary carrier mechanism in each of a plurality of spindle assemblies and passed through the hollow center of each yarn package by passing through a yarn passageway in a stationary carrier mechanism and a joining yarn passageway in a rotor mechanism and then radially out of the rotor mechanism for further travel through each spindle assembly in a well known manner for processing of the yarn, such as the insertion of a two-for-one twist therein.
Originally, threading of the yarn through such passageways in the carrier mechanism and the rotor mechanism of such textile yarn processing machines was accomplished manually. This manual threading operation was extremelly time consuming and cumbersome and reduced the efficiency of the machine operation.
More recently, pneumatically operated threading mechanisms have been proposed for such yarn processing machines, as disclosed in U.S. Pat. No. 3,731,478, issued May 8, 1973, and assigned to the assignee of the present invention. In the pneumatically operated threading mechanisms of this prior U.S. Patent, and aspirating or injector nozzle was provided in the rotating rotor mechanism of the spindle assembly which received air under pressure from a coupling or connecting member. In one embodiment illustrated in the aforementioned U.S. Patent, the coupling or connecting member, which was non-rotating, had to be coupled or connected with a non-axially positioned aperture in the bottom of the rotating rotor mechanism which required positioning of the rotor mechanism when stopped for threading-up of the spindle assembly in a predetermined position for effecting such coupling connection. Accordingly, if the rotor mechanism stopped in a position other than the predetermined position, the rotor mechanism had to be repositioned for effecting the aforesaid coupling for operating the threading mechanisms. Mechanisms for this repositioning of the rotor mechanism were provided for in U.S. Pat. Nos. 3,805,504; 3,805,507 and 3,834,144, all assigned to the assignee of the present invention.
In another embodiment of the aforesaid U.S. Pat. No. 3,731,478, stopping of the rotor mechanism in a predetermined position for alignment with the coupling or connecting member for operating the threading mechanisms was eliminated by disposing the coupling or connecting member axially through the rotor mechanism or whorl portion thereof for alignment with an axially positioned aperture or port in the yarn storage or reserve disc of the rotor mechanism. However, even with this arrangement, coupling was required between a stationary coupling or connecting member and the rotary yarn reserve disc of the rotor mechanism which presented problems in maintenance and proper operation of the pneumatic threading mechanisms.